Use of perturbants to facilitate incorporation and recovery of taggants from polymerized coatings

ABSTRACT

The invention provides methods for increasing the recoverability of taggants from an object. The methods include the steps of incorporating a taggant into a solution; mixing the solution including the taggant with a perturbant to form a first perturbant taggant solution; mixing the first perturbant taggant solution with a polymer to form a second perturbant taggant polymer solution; and applying the second perturbant taggant polymer solution to at least a portion of the object to form a taggant-coated object. Methods for authentication of a taggant marked object are also provided.

TECHNICAL FIELD

The present invention relates to methods for facilitating the inclusionof traceable taggants into polymers and for the recovery and detectionof such taggants without altering the aesthetic appearance of the objector the matrix of the object.

BACKGROUND

Despite being composed of relatively simple nucleotide building blocks,nucleic acids are capable of encoding a vast array of information:witness the human genome encodes all the information necessary for thesynthesis and assembly of all the components of the human body from theneural networks of the brain to the intricate structures of theskeleton, tissues and organs. Nucleic acids include deoxyribonucleicacid (DNA) and the more labile ribonucleic (RNA). Since nucleic acidsequences can be unique and complex, utilization of these particularcharacteristics in solving several common coding problems, such asauthenticating and tracking products and detecting counterfeit products,has recently attracted great interest.

Many product manufacturers utilize apparent qualities and definitivedesigns identifiable as “trade dress” to uniquely identify their highquality and high value products and thereby earn the trust of theircustomers. Others also add labels for anti-counterfeit purposes.Traditional anti-counterfeiting labels are generally formed frommaterials having particularly targeted physical or chemicalcharacteristics, for example, magnetic strips on checkbooks, laserholographs on credit cards, fluorescent ink on stock certificates, andheat-sensitive inks on confidential documents. Anti-counterfeitinglabels have also been made by adding specific antigens to objects thatneed to be identified, the antigens can then be detected with anantibody specific for the antigen. However, antigens and antibodies areproteins with characteristically poor stability under many environmentalconditions of temperature and humidity, and are prone to denaturation oreven degradation and consequently lose activity and can easily bedestroyed, thereby reducing the accuracy and reliability ofidentification.

Thus, nucleic acids, such as, for example, deoxyribonucleic acid (DNA)and ribonucleic acid (RNA) which encode essential hereditary informationhave been looked to as an improved alternative to commonly usedanti-counterfeiting labels and markers. DNA and RNA are polymersconsisting of a chain of nucleotides, referred to as “oligonucleotides”consisting of relatively short chains of up to say, twenty to fiftybases in length, or “polynucleotides” for longer chains. Theseoligonucleotide or polynucleotide chains consist of a number ofnucleotides linked together in sequence like beads on a string. Eachnucleotide consists of a ribose sugar-phosphate linked to one of onlyfour kinds of nitrogenous bases: adenine (often represented inabbreviated form as “A”), guanine (represented as “G”), cytosine(represented as “C”) and thymine (represented as “T”) in the case ofDNA; and adenine (A), guanine (G), cytosine (C) and uracil (U) in thecase of RNA. The oligonucleotides or polynucleotides share the samesugar-phosphate backbone. The 3′-hydroxyl group on the ribose sugar iscovalently bonded to the 5′-phosphate group of its neighboringnucleotide to form a chain structure with the planar nitrogenous basesprotruding from the chain not unlike the teeth of a comb.

The bases A, T, G and C in one oligonucleotides or polynucleotides chainare each capable of specific-pairing with another base a different chainto form a double stranded structure, or with the same chain to form adouble stranded loop or hairpin structure: Adenine specifically bondswith thymine through two hydrogen bonds in DNA (or with uracil in RNA)and cytosine specifically bonds with guanine through three hydrogenbonds. That is, T will bond to A and G to C bringing two nucleotidechains together to form a double strand, or two parts of a singlenucleotide chain together to form a double stranded region with eachstrand of the duplex connected by a loop.

An additional advantage of nucleic acids for use as markers or taggantsis that with the appropriate proper protection these molecules can bepreserved for long periods of time. Evidence from preserved specimens inglaciers, ice sheets, tar pits and bogs and marshes shows that DNA isresilient to degradation over thousands, and in some cases millions ofyears. Such evidence has been used to deduce information concerning theancestry and origins of ancient peoples as well as of plants andanimals. Protected marker DNA can also be stabilized in polymers forcoating of high value articles or objects of interest so as to survivelong periods of time and can then used for identification,authentication and tracking purposes. This ability to persist over longperiods of time coupled with very sensitive methods to detect lownumbers of molecules for instance by amplification using the polymerasechain reaction (PCR), makes nucleic acids, and DNA in particular, anattractive candidate for use as a marker. Moreover, nucleic acids offeran almost unlimited coding capacity since the number of possible uniquesequences increases fourfold with every additional base of the sequenceof the oligonucleotide or polynucleotide.

Sheu et al. (U.S. Pat. No. 7,115,301) disclosed that DNA can be used tomark solid articles or substances by incorporating DNA into a variety ofmedia that may be used for coating all or only part of an item ofinterest. Several media useful for such coatings disclosed by Sheu etal. include polycarbonate (PC), polymethyl methacrylate (PMMA),polystyrene (PS), and polypropylene (PP), or acrylic/epoxy resin-basedformulations. Often times a non-invasive or non-destructive samplingmethod is required for tagging of precious articles, such as paintingsor fragile articles, to preserve the aesthetic appearance and theintegrity of the marked articles. However, the recovery of the taggantmay be difficult or may provide such a low yield as to limit theapplicability of the method.

Polymers such as acrylic or epoxy based resinous polymers can be used asthe carrier media for taggants. Unfortunately, recovery of taggant fromthese polymers is often difficult and combinations of solvents have beendeveloped to deal with such issues (see for instance, Elwell, U.S. Pat.No. 4,278,557). However, for most applications employing the use of suchpolymers as coatings, total dissolution of the polymer is not necessary(nor is it usually possible) in order to achieve adequate recovery ofthe taggant from the polymer coating for verification purposes.Furthermore, the use of such solvents on precious articles or objects towhich the polymer is adhered may tarnish or damage the article or objectand is undesirable and is usually discouraged. An owner or a bona fidepurchaser interested in authentication of a purchase is unlikely toapprove the use of significantly invasive or destructive methods.

Therefore, there is a need in the art for a system permitting retrievalof taggants from polymerized coating on an article of value withoutsubjecting the tagged article to rigorous solvent treatments which maydisturb the aesthetics of the article.

SUMMARY

Exemplary embodiments of the present invention provide a methodology forextraction of taggants from a tagged article surface without damagingthe article or disturbing the aesthetics of its appearance.

In an exemplary embodiment of the present invention, a method forfacilitating the inclusion of traceable taggants into a polymer matrixuseful for coating an object is provided. The method includesincorporating a taggant into a solution, mixing the solution includingthe taggant with a perturbant to form a first perturbant taggantsolution, mixing the first perturbant taggant solution with a polymer toform a second perturbant taggant solution and applying the secondperturbant taggant solution to at least a portion of the object to forma taggant-coated portion of the object.

In another exemplary embodiment, the invention provides a method forincreasing recoverability of traceable taggants incorporated into apolymer matrix in a coating of an object. The method includesincorporating a taggant into a solution, mixing the solution includingthe taggant with a perturbant to form a first perturbant taggantsolution, mixing the first perturbant taggant solution with a polymer toform a second perturbant taggant solution and applying the secondperturbant taggant solution to at least a portion of the object, whereinthe recovery of the taggant is enhanced by the perturbant.

In still another exemplary embodiment of the present invention, a methodfor authenticating an object is provided. The method includes providingan object comprising a coating that includes a taggant such as a nucleicacid, a perturbant such as a polyol and a polymer coating; recoveringthe taggant from the object and verifying the authenticity of the objectby identifying the taggant.

In accordance with another exemplary embodiment of the presentinvention, an object marked with a taggant is provided. The object caninclude a coating covering at least a portion of the surface of theobject of interest; wherein the coating comprises a nucleic acid taggantand a perturbant in a polymer. Alternatively, the object can include anucleic acid taggant and a perturbant in a polymer uniformly distributedthroughout the object. In another alternative, the object may includethe nucleic acid taggant and a perturbant in a polymer non-uniformlydistributed in the object, such as in a portion of a coating and/or in aportion of the object that does not include a surface coating.

In accordance with yet another embodiment of the present invention, amethod for authenticating an object is provided. The method includesproviding an object having a coating that includes a taggant, at leastone perturbant, such as a polyol, recovering the taggant from the objectand verifying the authenticity of the object by identifying the taggantby any of the well known methods described in detail below.

In accordance with another embodiment of the present invention, anobject marked with a taggant is provided. The marked object includes acoating comprising a nucleic acid taggant, at least one perturbant (suchas a polyol) and a solvent; the coating may be cured and/or dried toprovide a coated object incorporating a taggant and the polyol orpolyols and any residual solvent after the curing and/or drying steps.

DETAILED DESCRIPTION

Definitions:

The term “taggant” as used herein is used to denote a substance that isaffixed to an object to indicate a property of the object, such as forinstance its source of manufacture. The object to be marked with thetaggant can be any solid traceable item, such as an electronic device,an item of clothing, paper, fiber, or fabric, or any other item ofcommerce, or cash or valuables, whether in storage or in transit.Alternatively, the item of commerce to be marked with the taggant can bea liquid, such as for instance an ink, a dye or a spray. In anotheralternative, the item of commerce can be a commodity item, such aspaper, metal, wood, a plastic or a powder. The taggant can be, forexample, specific to the company or the type of item (e.g. a modelnumber), specific to a particular lot or batch of the item (lot number),or specific to the actual item, as in, for instance, a serial numberunique to the item. In addition, the taggant can indicate any one ormore of a variety of other useful items of data; for example, thetaggant can encode data that indicates the name and contact informationof the company that manufactured the tagged product or item, the date ofmanufacture, the distributor and/or the intended retailer of the productor item. The taggant can also indicate, for example and withoutlimitation, component data, such as the source of the componentincorporated into the item or the identity of the production plant ormachinery that was used in the manufacture of the product or item; thedate that the product or item was placed into the stream of commerce,the date of acceptance by the distributor and/or the date of delivery tothe retailer and any other useful commercial, or other data such as forinstance personal information of the owner of a custom made item. Eachelement of data or indicia can be encrypted or encoded in the taggantand can be deciphered from taggant recovered from the object and decodedor decrypted according to the methods described herein. The decoded ordecrypted data can then be used to verify the properties of the object,or to authenticate the object, or to exclude counterfeit items.

The term “PCR” refers to a polymerase chain reaction. PCR is anamplification technology useful to expand the number of copies of atemplate nucleic acid sequence via a temperature cycling throughmelting, re-annealing and polymerization cycles with pairs of shortprimer oligonucleotides complementary to specific sequences borderingthe template nucleic acid sequence in the presence of a DNA polymerase,preferably a thermostable DNA polymerase such as the thermostable Taqpolymerase originally isolated from the thermophillic bacterium (Thermusaquaticus). PCR includes but is not limited to standard PCR methods,where in DNA strands are copied to provide a million or more copies ofthe original DNA strands (e.g. PCR using random primers: See forinstance PCR with Arbitrary Primers: Approach with Care. W. C. Black IV,Ins. Mol. Biol. 2: 1-6, Dec. 2007); Real-time PCR technology, whereinthe amount of PCR products can be monitored at each cycle (Real timequantitative PCR: C. A. Heid, J. Stevens, K. J. Livak and P. M.Williams, 1996 Genome Research 6: 986-994); Reverse transcription-PCRwherein RNA is first copied in DNA stands and thereafter the DNA strandsare amplified by standard PCR reactions (See for example: QuantitativeRT-PCR: Pitfalls and Potential: W. F. Freeman, S. J. Walker and K. E.Vrana; BioTechniques 26:112-125, January 1999).

The term “monomer” as used herein refers to any chemical entity that canbe covalently linked to one or more other such entities to form anoligomer or a polymer. Examples of “monomers” include nucleotides, aminoacids, saccharides, amino acids, and the like.

The term “nucleic acid” means a polymer composed of nucleotides whichcan be deoxyribonucleotides or ribonucleotides. These compounds can benatural or synthetically produced deoxyribonucleotides orribonucleotides. The synthetically produced nucleic acid can be of anaturally occurring sequence, or a non-natural unique sequence.

The terms “ribonucleic acid” and “RNA” denote a polymer composed ofribonucleotides. The terms “deoxyribonucleic acid” and “DNA” denote apolymer composed of deoxyribonucleotides.

The term “nucleotide” means a monomeric unit comprising a sugarphosphate, usually ribose-5′-phosphate or 2′-deoxyribose-5′-phosphatecovalently bonded to a nitrogen-containing base, usually, adenine (A),guanine (G), cytosine (C), or thymine (T) in the case of adeoxyribonucleotide, and usually, adenine (A), guanine (G), cytosine(C), or uracil (U) in the case of ribonucleotides.

The term “oligonucleotide” as used in this specification refers tosingle or double stranded polymer composed of covalently nucleotidemonomers forming a chain of from two to about twenty nucleotides inlength.

The term “polynucleotide” as used in this specification refers to singleor double stranded polymer composed of covalently nucleotide monomersforming a chain of generally greater than about twenty nucleotides inlength.

Nucleic acids having a naturally occurring sequence can hybridize withnucleic acids in a sequence specific manner. That is they canparticipate in hybridization reactions in which the complementary basepairs A:T (adenine:thymine) and G:C (guanine:cytosine) formintermolecular (or intra-molecular) hydrogen bonds and cooperativestacking interactions between the planar neighboring bases in eachstrand through Pi electrons, together known as Watson-Crick base pairinginteractions. The bases of the nucleic acid strands can also hybridizeto form non-Watson-Crick base pairs by so-called “wobble” interactionsin which G (guanine) pairs with U (uracil), or alternatively, I(inosine) pairs with C (cytosine), U (uracil) or A (adenine).

The term “identifiable sequence” or “detectable sequence” means anucleotide sequence which can by detected by hybridization and/or PCRtechnology by a primer or probe designed for specific interaction withthe target nucleotide sequence to be identified. The interaction of thetarget nucleotide sequence with the specific probe or primer can bedetected by optical and/or visual means to determine the presence of thetarget nucleotide sequence.

Embodiments of the present invention are listed below as non-limitingexamples illustrating the invention, but are not intended to be taken aslimits to the scope of the present invention, which will be immediatelyapparent to those of skill in the art.

Exemplary embodiments provide methods for increasing the recoverabilityof a taggant from an object without disturbing the appearance of theobject. Several exemplary embodiments of the present invention aredescribed in detail below.

Exemplary embodiments of the present invention also provide methods forauthenticating an object using taggants. For example, an exemplaryembodiment of the invention provides a method for increasing therecoverability of a taggant from an object; the method includesincorporating a taggant into a solvent, mixing the solution includingthe taggant with a perturbant to form a first perturbant taggantsolution, mixing the first perturbant taggant solution with a polymer toform a second taggant solution and applying the second taggant solutionto at least a portion of the object to form a taggant-coated portion ofthe object. The taggant can be soluble in an aqueous solution. Examplesof an aqueous soluble taggant include nucleic acids, saccharides,peptides and many proteins. Alternatively, the taggant can be insolublein an aqueous solution, or an organic solvent. Examples of a taggantthat is insoluble in aqueous solutions or organic solvents includeparticulate taggants, such as for instance, a up-converting phosphor(UCP) taggant, which may be any suitable UCP taggant, such as a nucleicacid-linked UCP.

An exemplary embodiment of the invention further provides a method forincreasing the recoverability of a taggant from an object; the methodincludes incorporating a taggant in an solution, mixing the solutionincluding the taggant with a perturbant to form a first perturbanttaggant solution, mixing the first perturbant taggant solution with apolymer to form a second taggant solution and applying the secondtaggant solution to at least a portion of the object to form ataggant-coated portion of the object. The solution into which thetaggant is incorporated can be an aqueous solution or an organicsolvent.

The polymer useful as coatings in the practice of the present inventionfor incorporating recoverable taggants into coatings of objects ofinterest can be any polymer that can be used to form a coating on anobject, such as for example, epoxy-acrylate, epoxy-urethane,polycarbonate (PC), polymethyl methacrylate (PMMA), polyurethane (PU),polystyrene (PS), polyamides (e.g. nylon 6, nylon 66), polypropylene(PP), polyvinyl chloride (PVC), polysulphones, polyvinylacetate (PVA),polyester (PES), polyethylene terephthalate (PET), polyethylene (PE),benzocyclobutene (BCB), high-density polyethylene (HDPE), polyvinylidenechloride (PVDC), low-density polyethylene (LDPE), high impactpolystyrene (HIPS), acrylonitrile butadiene styrene (ABS), phenolics(PF), melamine formaldehyde (MF), polyetheretherketone (PEEK),polyamides, polyetherimide (PEI), polyimide, polyether imide, polyetherketone imide, polylactic acid (PLA), polytetrafluoroethylene (PTFE),polymethyl pentene, polyether ketone, polyether, sulphone (PES),polyphenylene sulfide, polytetrafluoroethylene, butyl rubber,fluropolymers, silicones, Ionomers, moldable elastomers, ethylene vinylalcohol (EVOH), methalocene polymers and polyethylene naphthalate.

In addition, other polymers into which a taggant can be incorporatedaccording to the methods of the present invention and which can also beused for coating all or part of the surface of an object include, forexample, acrylic compounds such as polymethyl methacrylate (PMMA), atransparent thermoplastic synthetic polymer of methyl methacrylate, alsocalled acrylic glass; and acrylic copolymers such as polymethylmethacrylate-polyacrylonitrile copolymers; and the thermosettingepoxy-based polymer compounds such as epoxy-copolymers formed bypolymerization of a resin compound and a hardener or activator. Theresin is a monomer or short chain having an epoxy group at eachterminus. For example a commonly used epoxy resin is formed by areaction between a reactive epoxide such as epichlorohydrin (a.k.a.glycidyl chloride and 1-chloro-2,3-epoxypropane) and a reactive aromaticcompound, such as bisphenol-A. An example of a commonly used hardener istriethylenetetramine (TETA), although almost any polyamine can besubstituted. Alternatively, a mixture of two or more of any of theforegoing acrylic compounds and epoxy-based compounds can be used forthe coating according to an embodiment of the present invention.

In another exemplary embodiment, the epoxy-based compound that includesthe taggant of the present invention can include compounds and resinshaving two or more epoxy groups. These compounds may be in liquid,gel-like or in solid form. For example, epoxy-based compounds useful inthe practice of the present invention include epoxy resins such as:glycidyl ethers obtained by reacting epichlorohydrin with a polyhydricphenol such as bisphenol A, bisphenol F, bisphenol S, hexahydrobisphenolA, tetramethylbisphenol A, diallyl-bisphenol A, hydroquinone, catechol,resorcin, cresol, tetrabromobisphenol A, trihydroxybiphenyl,benzophenone, bisresorcinol, bisphenol hexafluoroacetone,tetramethylbisphenol A, tetramethylbisphenol F,tris(hydroxyphenyl)methane, bixylenol, phenol-novolac, orcresol-novolac; polyglycidyl ethers obtained by reacting epichlorohydrinwith an aliphatic polyhydric alcohol such as glycerin, neopentyl glycol,ethylene glycol, propylene glycol, butylene glycol, hexylene glycol,polyethylene glycol, or polypropylene glycol; glycidyl ether estersobtained by reacting epichlorohydrin with a hydroxycarboxylic acid suchas p-hydroxybenzoic acid or β-hydroxynaphthoic acid; polyglycidyl estersobtained from polycarboxylic acids such as phthalic acid, methylphthalicacid, isophthalic acid, terephthalic acid, tetrahydrophthalic acid,hexahydrophthalic acid, endomethylene tetrahydrophthalic acid,endomethylene hexahydrophthalic acid, trimellitic acid, and polymerizedfatty acids; glycidylamino-glycidyl ethers obtained from aminophenolsand aminoalkylphenols; glycidylamino-glycidyl esters obtained fromaminobenzoic acids; glycidylamines obtained from aniline, toluidine,tribromoaniline, xylylenediamine, diamino cyclohexane,bisaminomethyl-cyclohexane, 4,4′-diaminodiphenyl methane, and4,4′-diaminodiphenyl sulfone; and epoxydized polyolefins.

In an exemplary embodiment, the acrylic compound of the polymer forincorporation of the taggant according to the present invention can be,for example, an acrylate compound, an acrylate polymer, an acrylicfiber, an acrylic paint, an acrylic resin, an acrylic glass, or thelike.

In an exemplary embodiment of the present invention, the polymer is forexample, a natural polymer, a varnish, a polyurethane, a shellac or alacquer. The varnish, polyurethane, shellac or lacquer can be anysuitable varnish, polyurethane, shellac or lacquer, such as for instanceand without limitation, a polyurethane varnish from Minwax® Co., UpperSaddle River, N.J. Alternatively the polymer useful as a coating can bea natural polymer, such as beeswax, e.g. the beeswax available fromMountain Rose Herbs, Eugene, Oreg.

In another exemplary embodiment, the polymer is a component of apolymer-containing composition, such as for example, a printing ink. Forexample, in an exemplary embodiment, the ink may be a heat-curingepoxy-acrylate ink, such as Product No. 4408R or the 970 series TouchDry® pellet each from Markem®, Keene, N.H. Alternatively, the Artistri®P5000 +Series-Pigment Ink sold by Dupont® or an Epoxy Acrylate Ink, suchas Product No. 00-988, Rahn USA Corp. can be used.

The taggants of the present invention include, for example, nucleic acidtaggants. Nucleic acid is a general term for deoxyribonucleic acid (DNA)or ribonucleic acid (RNA), and can be synthetic, or derived from ananimal, a plant, a bacterium, a virus, a fungus, or a synthetic vectoror a fragment of any of the above-listed nucleic acids, etc. It shouldbe noted that a synthetic nucleic acid can have a sequence of anaturally occurring nucleic acid of an animal, plant, bacterium, fungus,virus or any other organism or synthetic vector. Alternatively, asynthetic nucleic acid can have a unique sequence not found in nature.It should be understood that such unique non-natural sequences may havestretches of sequences which are found in nature, but the entirenon-natural sequence is unique and is not found in any plant, animal orvirus or any other natural organism. In particular, the nucleic acidsequence encoding the element of data or indicia encrypted or encoded inthe taggant of the invention is a unique, non-natural sequence andthereby is adapted for use in authentication of an object of interest.

The taggant useful in the practice of the present invention can be anysuitable detectable or traceable taggant, for example, a chemical markeror a biological marker. In an embodiment of the methods of the presentinvention, the taggant is selected from a UV fluorophore, a ceramic IRmarker, DNA, an amino acid, a peptide, a protein, a lipid, a sugar, apolysaccharide, a pheromone, a scent, a trace element, a rare earthelement, or a combination of any two or more thereof.

In an embodiment of the present invention, the taggant includes anucleic acid. In one embodiment, the taggant consists essentially of DNAand no other significant component useful for identification orauthentication.

In addition, other taggants such as, for example, ultraviolet (UV)taggants, Up Converting Phosphor (UCP) infrared (IR) taggants, UV markertaggants, UV fluorophore taggants, ceramic IR marker taggants, proteintaggants, and/or trace element taggants can be used in combination withnucleic acid taggants. In an exemplary embodiment, the taggants used mayinclude, for example, a combination of DNA taggants, and an IRupconverting phosphor (UCP) taggant. Alternatively, in another exemplaryembodiment, the taggants used may include, for example, a combination ofDNA taggants, an IR upconverting phosphor (UCP) taggant and a UVtaggant. For example, in an exemplary embodiment, the IR (UCP) taggantcan be, for example, a green, a blue or a red (UCP) IR taggant, such asfor instance the Green IR Marker, Product No. BPP-1069; the Blue UCP,Product No. BPP-1070; or the Red UCP, Product No. BPP-1071 from BostonApplied Technologies Inc., Woburn, Mass.

The solution in which the soluble taggants are dissolved according tothe methods of the present invention can include, for example, water, TEbuffer (10 mM Tris·HCl, 1 mM EDTA), Tris-glycine buffer, Tris-NaClbuffer, TBE buffer (Tris-borate-EDTA), TAE buffer (Tris-acetate-EDTA)and TBS buffer (Tris-buffered saline), HEPES buffer(N-(2-Hydroxyethyl)piperazine-N′-ethanesulfonic acid), MOPS buffer(3-(N-Morpholino)propanesulfonic acid), PIPES buffer(Piperazine-N,N′-bis(2-ethanesulfonic acid), MES buffer(2-(N-Morpholino)ethanesulfonic acid), PBS (Phosphate Buffered Saline),PBP buffer (sodium phosphate+EDTA), TEN buffer (Tris/EDTA/NaCl), TBSTbuffer (Tris-HCl, NaCl, and Tween 20), PBST buffer (Phosphate BufferedSaline with Tween 20) and any of the many other known buffers used inthe biological and chemical sciences.

In an exemplary embodiment the perturbant useful for the practice of thepresent invention can be any suitable perturbant, such as a polyol or adiol or glycol, a starch or a pyrrolidone. The polyol can be anysuitable polyol, such as a polyethylene glycol polymer, for instance aPEG 200 i.e. a polyethylene glycol having an average molecular number of200 ethylene glycol units per chain (such as the PEG200 M_(n) 200Product No. P3015), Sigma-Aldrich, St. Louis, Mo. Alternatively, inanother embodiment, the polyethylene glycol can be a PEG 10,000 polyolpolymer such as the PEG10,000 Product No. P3015, M_(n) 10,000 fromSigma-Aldrich.

In another embodiment, the glycol useful as a perturbant according tothe invention can be any suitable glycol or diol, such as for instance,ethylene glycol, diethylene glycol, glycerol, methanediol, triethyleneglycol, propylene glycol from Sigma-Aldrich, or 1,2-butanediol or1,4-from butanediol from Fluka Analytical.

In another embodiment, the starch can be for example a hydroxylpropylstarch such as Zeina® B860 from Grain Processing Corp., Muscatine, IowaIn still another embodiment, the pyrrolidone perturbant of the inventioncan be any suitable pyrrolidone such as for instance an N-alkylpyrrolidone, or the caprylyl pyrrolidone surfactant: Surfadone® LP100available from Ashland Inc., Covington, Ky.

In an exemplary embodiment, the perturbant of the present invention canbe used in a solution containing the polymer and the taggant in anamount of about 0.1% to about 30% w/w of the taggant in the solution. Inanother exemplary embodiment, the perturbant of the present inventioncan be used in a solution containing the polymer and the taggant in anamount of about 1% to about 25% w/w of the taggant in the solution.Alternatively, the perturbant of the present invention can be used in asolution containing the polymer and the taggant in an amount of about 5%to about 20% w/w of the taggant in the solution. In another exemplaryembodiment, the perturbant of the present invention can be used in asolution containing the polymer and the taggant in an amount of about 7%to about 15% w/w of the taggant in the solution. In still anotherexemplary embodiment, the perturbant of the present invention can beused in a solution containing the polymer and the taggant in an amountof about %10 w/w of the taggant in the solution.

Alternatively, in one exemplary embodiment, the perturbant of thepresent invention can be used in a solution containing the polymer andthe taggant in an amount of about 0.1% to about 30% w/w of the taggantin the solution. In another exemplary embodiment, the perturbant of thepresent invention can be used in a solution containing the polymer andthe taggant in an amount of about 5% to about 30% w/w of the taggant inthe solution. Alternatively, the perturbant of the present invention canbe used in a solution containing the polymer and the taggant in anamount of about 10% to about 30% w/w of the taggant in the solution.

In one exemplary embodiment, the perturbant of the present invention canbe used in a solution containing the polymer and the taggant in anamount of about 1% to about 25% w/w of the taggant in the solution. Inan exemplary embodiment, the perturbant of the present invention can beused in a solution containing the polymer and the taggant in an amountof about 1% to about 20% w/w of the taggant in the solution. In anexemplary embodiment, the perturbant of the present invention can beused in a solution containing the polymer and the taggant in an amountof about 1% to about 15% w/w of the taggant in the solution. In anexemplary embodiment, the perturbant of the present invention can beused in a solution containing the polymer and the taggant in an amountof about 1% to about 10% w/w of the taggant in the solution.

Without wishing to be bound by theory, it is believed that theperturbants of the present invention create microcrevices andmicropockets and microenvironments in the polymerized polymerfacilitating recovery of the taggant (e.g. a DNA taggant) moreefficiently than from polymerized coatings lacking such perturbants.

The objects of interest coated with the taggants according to exemplaryembodiments of the present invention include, for example, ceramicsurfaces, plastic films, vinyl sheets, antiques, items of jewelry,identification cards, credit cards, magnetic strip cards, paintings,artwork, souvenirs, sports collectibles and other collectibles. Theauthenticity of these objects can then be verified by recovering andidentifying the taggants coated thereon through, for example, methodsdescribed in further detail below.

The coating that includes or incorporates a taggant of the inventionwhich can be applied to an object of interest can be any suitablecoating which is stable and capable of incorporating the taggant, forexample, a plastic, a varnish, a polyurethane, a shellac or a lacquer.Alternatively, the coating can be beeswax.

Alternatively, the coating of the present invention applied to an objectof interest can be, for example, an ink, a paint, a sealer, a glue, acoating containing one or more dyes, one or more dyestuffs, or one ormore pigments, and other such common coatings.

In another embodiment of the present invention, the method comprisesincorporating or dissolving the taggant in a solution to form a taggantsolution prior to mixing the nucleic acid taggant with the perturbant,mixing the first solution with a polymer to form a second solution, andapplying the second solution to at least a portion of the object to forma taggant-coated portion of the object, wherein the taggant isrecoverable from the object.

In one embodiment, the second solvent, is a non-polar solvent. In oneembodiment, the second solvent is selected from the group consisting ofmethyl ethyl ketone (MEK), acetone, an alcohol, such as for instancemethanol, ethanol, n-propanol, isopropanol, n-butanol, or isobutanoletc. or an ether, such as for instance dimethylether, methylethyl etherand diethyl ether etc. Alternatively, the second solvent can be acombination of two or more ketones, alcohols, or ethers. In anotheralternative the second solvent can be a combination of any two or moreof the above solvents.

In another embodiment, the taggant includes an IR upconverting phosphor(UCP) taggant and a DNA taggant, and wherein the perturbant is a polyol.

In still another embodiment, the polymer is a varnish, a polyurethane, ashellac or a lacquer.

In one embodiment of the present invention, the solution enhancerincludes at least one polyol. The polyol can be any suitable polyol,such as for ethylene glycol, diethylene glycol, glycerol, methanediol,1,2-butanediol, 1,4-butanediol, triethylene glycol, propylene glycol,and polyethylene glycol (PEG). The polyethylene glycol can be of anysuitable size, such as for instance and without limitation, PEG 200, PEG400, PEG 600, PEG 2000, PEG 3350 or PEG 10,000.

For example, the polyethylene glycol may be any suitable polyethyleneglycol available from Sigma-Aldrich, St. Louis, Mo. The PEG200 may be,for example M_(n) 200, Product No. P3015. The PEG 400 may be, forexample, M_(n) 400, Product No. 202398. The PEG600 may be, for example,M_(n) 600 waxy moist solid, Product No. 202401. The PEG2,000 may be, forexample, M_(n) 1900-2200 solid flakes, Product No. 295906-250G. ThePEG3350 may be, for example, M_(n) 3000-3700, Product No. 83272. Inanother exemplary embodiment, the PEG10,000 may be, for example, M_(n)10,000, Product No. 309028.

In another embodiment, the polymer is selected from the group consistingof polycarbonate (PC), polymethyl methacrylate (PMMA), polyurethane(PU), polystyrene (PS), nylon or polypropylene (PP) all of which arereadily commercially available. In another embodiment, the polymerincludes a first solvent comprising a polymeric compound thepolymerization of which can be initiated and hardened by heat, UV or acatalyst.

In one embodiment, the method of the present invention further includescuring or drying the second solution applied on the object to provide acoating including the taggant. The coating can be over all or part ofthe object to be identified, validated, authenticated, or tracked.

After coating an object with the taggant-containing polymer according tothe methods of the present invention, the coating can be, dried or curedsuch that the coating adheres to the object, thereby providing theobject with authentication, tracking and anti-counterfeiting functions.

In exemplary embodiments of the present invention, the taggant can berecovered from the taggant-coated portion of the object withoutdisturbing the appearance of the object. For example, the taggant can berecovered from the taggant-coated portion of the object by swabbing asurface of the object. In one exemplary embodiment, the object may beswabbed with a cotton swab, a cotton ball, a cotton fabric, a filter ora tissue paper, or any other suitable sampling medium. For example, inan exemplary embodiment the taggant is recovered from the taggant-coatedportion of the object using any suitable solvent on an applicator suchas a cotton-tipped applicator. The solvent can be any suitable solventavailable from reagent vendors such as Sigma-Aldrich. Suitable solventsinclude, for instance, ethanol, methanol, propanol, toluene, xylene andmethylethylketone (MEK, 2-butanone), to name but a few. Other suitablecommonly available solvents will be readily identifiable by those ofskill in the art.

In an embodiment of the invention, the polymer into which the polymerinto which the first solution containing the solution enhancer andtaggant is mixed, can be gasoline, diesel fuel, such as the gasoline ordiesel fuel, a lubricant oil such as motor oil, heating oil, kerosene,jet fuel or unrefined crude oil, and the like.

Exemplary embodiments of the present invention also provide a method forauthenticating an object which includes providing an object comprising acoating comprising a taggant, a perturbant and a polymer, recovering thetaggant from the object for identification, tracking, or verifying theauthenticity of the object by identifying the unique taggant. In oneembodiment, the unique taggant is a DNA taggant having a unique DNAsequence and the unique non-natural DNA sequence is stored in a databasethat matches the unique DNA sequence to the data elements correspondingto the object which is coated with the unique taggant. The database canin turn be located on a computer that can be accessed in order tolocate, track, authenticate and verify the identity of the tagged objectfrom which the taggant was recovered.

DNA taggants useful in the examples described below include any suitableDNA taggant, such as for instance, in one embodiment, the DNA taggant isa double stranded DNA oligomer having a length of between about 40 basepairs and about 1000 base pairs. In other embodiments the DNA taggant isa double stranded DNA oligomer with a length of between about 80 and 500base pairs. In another embodiment the DNA taggant is a double strandedDNA oligomer having a length of between about 100 and about 250 basepairs. Alternatively, the DNA taggant can be single-stranded DNA or anysuitable length, such as between about 40 bases and about 1000 bases;between about 80 and 500 bases; or between about 100 and about 250bases. The DNA taggant can be natural DNA, whether isolated from naturalsources or synthetic; or the DNA taggant can be a synthetically producednon-natural sequence. All or a portion of the DNA may comprise anidentifiable sequence.

In one exemplary embodiment, the DNA taggant is identifiable by anysuitable detection and/or identification method such as for example,hybridization with a taggant-sequence specific nucleic acid probe, an insitu hybridization method (including fluorescence in situ hybridization:FISH), amplification using a polymerase chain reaction (PCR), such asquantitative/real time PCR and detection of the amplified sequences(amplicons) by any of the variety of standard well known methods.

For example, in the PCR identification method, the nucleic acidtaggants, e.g., DNA taggants recovered from the object are amplified bypolymerase chain reaction (PCR) and resolved by gel electrophoresis.Since the sequence of the nucleic acid taggants of the present inventionare unique and specific to the tagged object, the original nucleic acidwill be amplified only by use of primers having specific sequencescomplementary to a portion of the unique taggant sequence. Through thisprocedure, if the examined object carries the original nucleic acid, thePCR procedure will amplify extracted nucleic acid to produce ampliconsof a predetermined size and a sequence identical to a portion of theoriginal nucleic acid sequence of the taggant. In contrast, if thesample recovered from the examined object does not include the uniquenucleic acid corresponding to the authentic object, there will likely beno amplified nucleic acid product, or if the primers do amplify therecovered nucleic acid to produce one or more random amplicons, theseone or more amplicons cannot have the unique taggant nucleic acidsequence from the authentic object. Furthermore, the random ampliconsderived from counterfeit articles are also of random lengths and thelikelihood of producing amplicons of the exact lengths specified by thetaggant-specific primers is vanishingly small. Therefore, by comparingthe sizes of PCR products, the authenticity of labeled objects can beverified, non-authentic objects can be screened and rejected andanti-counterfeit screening purpose is then achieved.

The number of amplicons amplified and the lengths of the amplicons canbe determined after any molecular weight or physical dimension-basedseparation, such as for instance and without limitation, gelelectrophoresis in any suitable matrix medium for example in agarosegels, polyacrylamide gels or mixed agarose-polyacrylamide gels and theelectrophoretic separation can be in a slab gel or by capillaryelectrophoresis.

EXAMPLES

It should be understood that following examples set forth are intendedto be illustrative only and that exemplary embodiments of the presentinvention are not limited to the conditions or materials recitedtherein.

The following examples illustrate embodiments of the present inventionto enhance recoverability of a taggant from a taggant coating on acoated object according the following method: incorporating ordissolving a taggant into an solution, mixing the taggant solution witha perturbant to form a first perturbant taggant solution; then mixingthis perturbant taggant solution with a polymer to form a perturbanttaggant polymer solution; and coating at least a portion of the objectto form a taggant-coated object.

Example 1 Inclusion of UV Taggant and DNA Taggant in Solvent BasedTopcoat Varnish and the Recovery of the DNA Taggant

Five percent solution (w/w) of UV taggant and DNA taggant at 1 ng/mlfinal concentration are first mixed together and sufficientSurfadone®LP100 is added to reach a concentration of 7% of final volume(v/w) before adding to 1 L of varnish. The mixture is paddle blended for10 min and applied onto plastic film to dry in an oven at 60° C.overnight. The varnish film is sampled using a cotton swab dipped in 30%EtOH solution and swabbed across the varnished surface several times. UVtaggant is picked up by the swab without disturbing the appearance ofthe varnish and the extracted sample transferred by the swab is used forDNA authentication.

Example 2 Inclusion of Up Converting Phosphor (UCP) IR and DNA Taggantsin Polyurethane Varnish and Recovery Thereof

Five percent (w/w) of UCP IR and DNA taggant (which may be in the formof a DNA-linked UCP taggant) at 5 ng/ml final concentration are firstmixed together and added to 10 g molten PEG10,000 (average molecular no:M_(n) 10,000, Product No. 309028, Sigma-Aldrich) before adding to 1 L ofpolyurethane varnish (Minwax® Co., Upper Saddle River, N.J.). Themixture is then paddle blended for 10 min and applied onto vinylsheet(s) to dry in 60° C. oven for 1 hour. The varnished film is sampledby using a cotton swab (Cotton tipped Applicator No. 25-826 5WC PuritanMedical Products, Guilford, Me.) dipped in 100% MEK solution and swabbedacross the varnished surface for several times. UCP-linked DNA taggantis picked up by the swab without disturbing the appearance of theobject, and the DNA is then authenticated by PCR-based analysis.

Example 3 Inclusion of Particulate DNA Taggants in Natural VarnishesSuch as Shellac and the Recovery Thereof

DNA taggant at 5 ng/ml final concentration is added to 10 g PEG 200before adding to 1 L of varnish. The mixture is paddle blended for 10minutes and applied onto a plastic film and allowed to cure at roomtemperature. The varnish film is then sampled by using a cotton swabdipped in 20% EtOH (Sigma-Aldrich) and swabbed across the varnishedsurface several times. The DNA taggant is picked up by the swab withoutdisturbing the appearance of the varnish, and the DNA is thenauthenticated by PCR based analysis.

Example 4 Inclusion of UCP IR and DNA Taggants in Heat Cured PrintingInk and the Recovery Thereof

Ten percent (w/w) of UCP IR taggant linked DNA taggant at 10 ng/ml finalconcentration are first mixed together and added to 5% g hydroxypropylstarch before adding to 1 L of printing ink. The mixture is then blendedfor 10 min and used for the printing on ceramic surfaces and dried in120° C. oven for 24 hours. The dried ink is sampled by using a cottonswab dipped in 100% MEK and swabbed across the printed surface severaltimes. The UCP-linked taggant is picked up by the swab withoutdisturbing the appearance of the print, and the DNA is thenauthenticated utilizing a PCR-based assay.

Example 5 Inclusion of UCP IR and DNA Taggants in UV Cured Printing Inkand the Recovery Thereof

Five percent (w/w) of UCP IR taggant and DNA taggant are first mixedtogether and added to 50 g of melted PEG 10,000 before being adding to 1L of printing ink. The mixture is then paddle blended for 10 min andprinted on ceramic surfaces and subjected to high intensity mercury lampfor 5 sec. to cure. The cured ink is then sampled using a cotton swabdipped in 100% MEK solution and swabbed across the printed surfaceseveral times. The UCP taggant is picked up by the swab withoutdisturbing the appearance of the print, and the DNA is thenauthenticated by utilizing a PCR based assay.

Example 6 Inclusion of DNA Taggants in a Two Component Glue System andRecovery Thereof

One of the components of the two component glue system acts as catalystto cure the glue. One percent (w/w) of UCP IR taggant, one percent (w/w)UV marker, and DNA taggant at 20 ng/ml final concentration are firstmixed together and added to 50 g of propylene glycol before adding to 1L of one or both components (resin and hardener) of the glue. Twocomponents of the glue are then mixed and allowed to cure. The curedglue is then sampled using a cotton swab dipped in 100% MEK and swabbedacross the printed surface several times. The taggant is picked up bythe swab without disturbing the appearance of the cured glue block, andthe DNA is then authenticated by PCR assay.

Example 7 Inclusion of Up Converting Phosphor (UCP) IR and DNA Taggantsin Polyurathane Varnish and the Recovery Thereof

Five percent (w/v) of UCP IR taggant (e.g. ADA-3253 from H. W. SandsCorp., Jupiter, Fla.) and DNA taggant at 5 ng/ml final concentration arefirst mixed together and added to 50 ppm of ethylene glycol beforeadding to 1 L of solvent-based polyurethane varnish. The mixture is thenblended and applied onto vinyl sheet(s) to cure under an infrared lightstation for five minutes. The varnished film is sampled by using acotton swab dipped in 100% EtOH and swabbed across the varnished surfaceseveral times. UCP taggant is picked up by for DNA authenticated byPCR-based analysis.

Example 8 Inclusion of UV Taggant and DNA Taggant in Solvent BasedTopcoat Varnish and the Recovery Thereof

Five percent (w/v) of water soluble UV taggant and DNA taggant at 1ng/ml final concentration are first mixed together and added to 5% ofPEG2,000 to the final volume (w/v) before adding to 1 L of MEK basedvarnish. The mixture is paddle blended for 10 min and applied ontoplastic film to dry in 60° C. oven overnight. The varnish film issampled by using a cotton swab dipped in 30% EtOH solution and swabbedacross the varnished surface several times. UV taggant along with theDNA taggant is picked up by the swab without disturbing the appearanceof the varnish, and the swab is then used for DNA authentication.

Example 9 Inclusion of UCP IR and DNA Taggants in UV-Cured Printing Inkand the Recovery Thereof

Five percent (w/v) of UCP IR taggant and DNA taggant at 10 ng/ml finalconcentration are first mixed together and added to 25 mL of PEG400before being added to 1 L of MEK-based printing ink. The mixture is thenpaddle blended for 10 min and used for printing on epoxy surfaces andsubjected to heat from a high intensity mercury lamp for 1 minute tocure. The cured ink is then sampled using a cotton swab dipped in 100%Ether and swabbed across the printed surface several times. The UCPtaggant is picked up by the swab without disturbing the appearance ofthe print, and the DNA is authenticated by a PCR-based assay.

Example 10 Inclusion of Particulate DNA Taggants in Varnish or Shellacand the Recovery Thereof

DNA taggant at 5 ng/ml final concentration is added to 10 g glycerolbefore adding to 1 L of varnish (Minwax® Co., Upper Saddle River, N.J.).The mixture is paddle blended for 10 minutes and applied onto a plasticfilm for room temperature curing. The varnish film is then sampled usinga cotton swab dipped in 100% acetone and swabbed across the varnishedsurface several times. The DNA taggants are picked up by the swabwithout disturbing the appearance of the varnish, and the DNA is thenauthenticated by a PCR-based assay.

Example 11

Inclusion of DNA Taggants in Lubricant and the Recovery Thereof

10 ng/ml (final concentration) DNA taggant at is mixed with 100 uLPEG400 average M_(n) 400, Product No. 202398, Sigma-Aldrich) beforeincorporation of 1 L of lubricant (Havoline® motor oils sold by ChevronUSA). The DNA is purified from the lubricant and the DNA is thenauthenticated utilizing a PCR-based assay.

Example 12

Inclusion of DNA Taggants in Beeswax and the Recovery Thereof

10 ng/ml of DNA taggant (final concentration) is added to 100 ppm ofmolten PEG3350 average M_(n) 3000-3700, Product No. 83272,Sigma-Aldrich) before being added to 1 L of molten beeswax(Mountainroseherbs.com, Eugene, Oreg.) The DNA is purified from the waxand the DNA is then authenticated by utilizing a PCR based assay

Example 13 Inclusion of DNA Taggants in Solvent-Based Inkjet Inks andRecovery Thereof

10 ng/ml of DNA taggant (final concentration) is added to 1% of PEG200average M_(n) 200, Product No. P3015, Sigma-Aldrich) before being mixedinto 1 L of a solvent based inkjet ink (such as the 970 series TouchDry® pellet; or the 4408R heat-curing ink sold by Markem®, Keene, N.Y.;the Artistri® P5000 +Series-Pigment Ink sold by Dupont®, or the EpoxyAcrylate Ink, Product No. 00-988, Rahn USA Corp.). The DNA taggant ispicked up by swabbing with an MEK soaked cotton tipped applicator andthen the DNA is authenticated using a PCR-based analysis method.

The full scope of the invention will be appreciated in view of the U.S.Patents and references cited in this specification, the entiredisclosures if which are hereby incorporated by reference.

Having described exemplary embodiments of the present invention, it isfurther noted that it will be readily apparent to those of reasonableskill in the art that various modifications may be made withoutdeparting from the spirit and scope of the invention which is defined bythe metes and bounds of the appended claims.

1-20. (canceled)
 21. A method for authenticating an object, comprising:providing an object having a coating comprising a taggant, a perturbantand a polymer; wherein the taggant comprises a nucleic acid; wherein theperturbant comprises: (i) one or both of a polyol and surfactant; and(ii) one or both of a hydroxypropyl starch and a pyrrolidone compound;wherein the polymer comprises one or more of a polyurethane, a shelac, alacquer, an acrylic compound and an epoxy-based compound; recovering thetaggant from the object; and verifying the authenticity of the object byidentifying the taggants.
 22. The method of claim 21, wherein thenucleic acid taggant comprises DNA.
 23. The method of claim 22, whereinthe taggant further includes one or more of an upconverting (UCP), a UVfluorophore, a ceramic IR marker, an amino acid, a protein, a pheromone,a scent, a trace element and a rare earth element.
 24. The method ofclaim 23, wherein the taggant consists essentially of DNA and one orboth of an IR upconverting phosphor (UCP) and a UV fluorophore.
 25. Themethod of claim 21, wherein the perturbant consists essentially of apolyol, a hydroxypropyl starch, and a pyrrolidone compound.
 26. Themethod of claim 25, wherein the polyol of the perturbant comprisespolyethylene glycol (PEG), polypropylene glycol, or a mixture ofpolyethylene glycol (PEG) and polypropylene glycol.
 27. The method ofclaim 26, wherein the polyol of the perturbant comprises one or both ofPEG 200 and PEG 10,000.
 28. The method of claim 21, wherein the at leastone polyol is selected from the group consisting of ethylene glycol,diethylene glycol, triethylene glycol, propylene glycol, polyethyleneglycol, and polypropylene glycol.
 29. The method of claim 22, whereinthe DNA taggant recovered from the object is authenticated using amethod comprising PCR or FISH.
 30. The method according to claim 29,wherein the DNA taggant is authenticated in a PCR reaction using primersspecific to the DNA taggant to produce specific amplicons, andidentifying of the number of the specific amplicons and the length ofeach of the specific amplicons amplified in the polymerase chainreaction.
 31. The method of claim 21, wherein the perturbant is in arange from about 0.1% w/w to about 30% w/w of the polymer.
 32. Themethod of claim 31, wherein the perturbant is in a range from about 1%w/w to about 20% w/w of the polymer.
 33. The method of claim 32, whereinthe perturbant is in a range from about 1% w/w to about 10% w/w of thepolymer.
 34. A method for authenticating an object, comprising:providing an object having a coating comprising a taggant, a perturbantand a polymer; wherein the taggant comprises a nucleic acid; wherein theperturbant comprises: (i) one or both of a polyol and surfactant; and(ii) one or both of a hydroxypropyl starch and a pyrrolidone compound;wherein the polymer comprises one or more of wherein the polymer isselected from the group consisting of epoxyacrylate, epoxyurethane,polycarbonate (PC), polymethyl methacrylate (PMMA), polyurethane (PU),polystyrene (PS), polyamide, polypropylene (PP), polyvinyl chloride(PVC), polysulphone, polyvinylacetate (PVA), polyester (PES),polyethylene terephthalate (PET), polyethylene (PE), benzocyclobutene(BCB), high-density polyethylene (HDPE), polyvinylidene chloride (PVDC),low-density polyethylene (LDPE), high impact polystyrene (HIPS),acrylonitrile butadiene styrene (ABS), phenol-formaldehyde resins (PF),melamine formaldehyde (MF), polyetheretherketone (PEEK), polyetherimide(PEI), polyimide, polyether imide, polyether ketone imide, polylacticacid (PLA), polytetrafluoroethylene (PTFE), polymethyl pentene,polyether ketone, polyether sulphone, polyphenylene sulfide,polytetrafluoroethylene, butyl rubber, fluropolymers, silicones,ionomers, moldable elastomers, ethylene vinyl alcohol (EVOH),metallocene polymers and polyethylene naphthalate; recovering thetaggant from the object; and verifying the authenticity of the object byidentifying the taggants.
 35. The method of claim 34, wherein thenucleic acid taggant comprises DNA and the DNA recovered from the objectis authenticated using a method comprising PCR or FISH.
 36. The methodof claim 34, wherein the perturbant is in a range from about 0.1% w/w toabout 30% w/w of the polymer.
 37. An object marked with a taggantcomprising a coating comprising a taggant, a perturbant, and a polymer;wherein the taggant comprises a nucleic acid; wherein the perturbantcomprises: one or both of a hydroxypropyl starch and a pyrrolidonecompound; and wherein the polymer comprises one or more of apolyurethane, a shelac, a lacquer, an acrylic compound and anepoxy-based compound.
 38. The object according to claim 37, wherein theperturbant further comprises one or both of a polyol and surfactant. 39.The method of claim 38, wherein the polyol of the perturbant comprisespolyethylene glycol (PEG), polypropylene glycol, or a mixture ofpolyethylene glycol (PEG) and polypropylene glycol.
 40. The method ofclaim 39, wherein the polyol of the perturbant comprises one or both ofPEG 200 and PEG 10,000.